Casein glue



Patented Apr. 19, 1927.

UNITED STATES PATENT orrics.

ALFRED CARL MABWIN, OF CHICAGO, ILLINOIS, ASSIGNO R TO WESTERN ELECTRIC GOMPANY, INQOBPORATED, OF NEW YORK, N. Y., A CORPORATION OI NEW YORK.

CASEIN GLUE.

No Drawing.

This invention relates to the production of casein solution or casein glue suitable for cementing together wooden or other surfaces, and its object is to provide such a glue containing ingredients of such character and so proportloned that where it comes into contact with tools operating on articles cemented therewith, theglue will occasion minimum wear thereon, whereby a longer life of the tools is obtained.

A further object of the invention is to produce such a glue, which is waterproof,

smooth, easy to apply, and which has sufficiently slow setting properties as to render it usable, after mixing, during an average working day.

In the production of casein glues it has beenthe practice to include arelatively large amount of alkaline earth hydroxide such as hydrated lime tomake the glue insoluble.- Where the cemented work is sub-- 'jected to the cutting action of tools, glue having a large alkaline earth hydroxide content causes considerable wear on the tools, thereby lessening the effective working life thereof. For these reasons in the compound of the present invention only about per cent of alkaline earth hydroxide such as hydrated lime is combined with 75 per cent of casein. With the proportions of casein and lime above specified about 7 percent of caustic alkali, such as caustic soda, and about 8 per cent of a water soluble alkaline salt, of an alkali, such as trisodium phosphate, are added. About parts by weight of water are added to about 10 parts by weight of the above mixture, the resulting fluid mass being the finished glue. The percentage composition of the finished product is therefore approximately casein alkaline earth hydroxide 3 ,g%; caustic alkali 2%%; water soluble alkaline salt of an alkali 235% and water 66%%.

In place of hydrated lime other alkaline earth hydroxides such as barium hydroxide, strontium hydroxide and magnesium hydroxide may be used, and in place of caustic soda other caustic alkali such as caustic potash and ammonium hydroxide may be employed. Other alkaline salts maybe sub- Lpplication filed June 24,

.and easy to apply.

1922 Serial No. 570,731,

solvents for the casein and therefore retard the setting action of the lime so as to give the mixture a long working life. The caustic soda renders the compound smooth As above stated, the small amount of lime included renders the mixture less harmful to tools than any other glues heretofore produced, while the caustic soda and trisodium phosphate in the proportions specified give the compound a smooth conslstency and render it workable, after mixin for a period of at least eight hours un er ordinary conditions.

What is claimed is: p 1. A casein glue composition consisting of about 25% casein, alkaline earth hydroxide about -3 alkali and water soluble alkaline salt of an alkali 5%, and water.

2. A casein glue com osition consisting of about 25 er cent casein, alkaline earth hydroxide a out 3 per cent, caustic alkali about 2% per cent, water soluble alkaline salt of an alkali about.2% per cent, and

water.

3. A casein glue composition consisting of casein, hydrated lime, caustic soda, trisodium hosphate and water, the casein and hydrated lime being present in the composition in the ratio of about 7.5 parts to 1 part, respectively.

4. A casein glue composition consisting of about 25 per cent casein, hydrated lime about 3% per cent, caustic-soda about 2% per cent,

'trisodium phosphate about 2% per cent, and water. I v

i In witness whereof, I hereunto subscribe my name this 16th day of June A. D., 1922.

' ALFRED CARL MARWIN. 

